Swing arm for rotary water sprinkler

ABSTRACT

A SWING ARM FOR A ROTARY WATER SPRINKLER. THE SWING ARM HAS A SPOON-LIKE PORTION INTO WHICH A JET OF WATER FROM A NOZZLE OF THE SPRINKLER IMPINGES. THE SPRINKLER MAY BE OF THE KIND HAVING A SECTORING MECHANISM OPERATIVE TO CAUSE THE SEING ARM TO EFFECT OSCILLATIION OF THE SPAINKLER THROUGH A LIMITED SECTOR. TO REDUCE THE IMPACT OF THE SWING ARM ON A STROP A THE END OF THE SECTORING OPERATION, THE SPOON-LIKE PORTION HAS A DEFLECTOR SURFACE EXTENDING ALONG THE LENGTH OF THE SPOON FROM THE END NEARER TO THE NOZZLE AND AN APERTURE EXTENDING LONGITUDINALLY OF THE BOWL OF THE SPOON-LIKE PORTION ALONG A MAJOR PART OF THE DEFLECTOR SURFACE DOWNSTREAM OF AN INITIAL PART WHICH EXTENDS ACROSS THE WIDTH OF THE SPOON, WHEREBY ONLY PART OF THE JET FROM THE NOZZLE WILL FLOW THROUGH THE APERTURE INTO THE BOWL OF THE SWING ARM, THE REMAINDER BEING GUIDED BY THE DEFLECTOR SURFACE PAST THE SPOON-LIKE PORTION WITHOUT ENTERING THE BOWL THEREOF. THE SWING ARM OF THIS INVENTION ALSO GIVES AN IMPROVED WATER DISTRIBUTION AND SO CAN BE USED WITH A WATER SPRINKLER NOT HAVING SECTORING MECHANISM.

p 20, 1 B. A. LEWIS 3,606,163

SWING AR" FOR, ROTARY WATER SPRINKLER Filed Jan. 12, 1970 4 Sheets-Sheet 1 PRIOR ART PRIOR ART Sept. 20, 1971 B. A. LEWIS 3,606,163

' swme ARI FoR ROTARY WATER SPRINKLER Filed Jan. 12. 1970 4 Sheets-Shoots FIG. 5.

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Sept. 20, 1971 a. A. LEWIS 3,606,163

' swme m FOR norm: vmma sramgnnn Filed Jan. 12, 1970 4 Sheets-Shoat 5 DEPTH OF WATER L .-0. -W ..1 DISTANCE FROM SPRINKLER FlG.9.

@DEPTH OF WATER DISTANCE FROM SPRINKLER NVENTDE BmAN ALCEE'b Lawns A'rr'orrwsr Sept. 20,1971 B. A. LEWIS 7 3,505,153

' SWING ARI FOR ROTARY WATER SPRINKLER Filed Jan. 12. 1970 4 Sheets-Sheet 4 BmAN ALrrznb Lawns United States Patent 3,606,163 SWING ARM FOR ROTARY WATER SPRINKLER Brian Alfred Lewis, Ringwood, England, assignor to Wright Rain Limited of Crowe, Ringwood, Hampshire,

England Continuation-impart of abandoned application Ser. No.

739,437, June 24, 1968. This application Jan. 12, 1970,

Ser. No. 2,173

Int. Cl. Bb 3/02 US. Cl. 239230 4 Claims ABSTRACT OF THE DISCLOSURE A swing arm for a rotary water sprinkler. The swing arm has a spoon-like portion into which a jet of water from a nozzle of the sprinkler impinges. The sprinkler may be of the kind having a sectoring mechanism operative to cause the swing arm to effect oscillation of the sprinkler through a limited sector. To reduce the impact of the swing arm on a stop at the end of the sectoring operation, the spoon-like portion has a deflector surface extending along the length of the spoon from the end nearer to the nozzle and an aperture extending longitudinally of the bowl of the spoon-like portion along a major part of the deflector surface downstream of an 1n1t1al part which extends across the width of the spoon, whereby only part of the jet from the nozzle will fiow through the aperture into the bowl of the swing arm, the remainder being guided by the deflector surface past the spoon-like portion without entering the bowl thereof. The swing arm of this invention also gives an improved water distribution and so can be used with a water sprinkler not having sectoring mechanism.

This application is a continuation-in-part application of my application Ser. No. 739,437, filed June 24, 1968, now abandoned.

The invention relates to a rotary water sprinkler of the kind having a rotatable tubular body carrying a nozzle to which water is to be supplied, a swing arm mounted for rotation relatively to the sprinkler body and having a spoon-like portion into the bowl of which a jet discharged by the nozzle is arranged to impinge to effect turning of the swing arm about its axis of rotation against the force of a torsion spring, until the latter causes the swing arm to turn in the reverse direction to strike the tubular body and thereby to turn the latter in an angular increment in said reverse direction.

Rotary water sprinklers of the foregoing kind may also be provided with a sectoring mechanism to lock the swing arm to the sprinkler body during part of its angular movement during which the sprinkler body and the swing arm will turn in unison under the impact of the jet from the nozzle, the movement of the tubular body in angular increments in said reverse direction being effected only through a predetermined sector when the swing arm is not locked to the sprinkler body. When the sectoring mechanism is not operative to lock the swing arm to the sprinkler body, or where it is not provided, the incremental angular movement of the tubular body will be effected continuously in said reverse direction during discharge of the nozzle.

A rotary water sprinkler of the foregoing kind having a sectoring mechanism and known hitherto is briefly described herein with reference to FIGS. 1 and 2 of the accompanying drawings, of which:

FIG. 1 is an elevation of the known sprinkler, and

FIG. 2 is a plan view of the sprinkler shown in FIG. 1.

The known sprinkler comprises a body 2 supported by a pipe coupling 1 to be screwed to a stationary standpipe (not shown). The body 2 carries a fixed arm 3 supporting a nozzle 4 which is supplied with water from the standpipe through the coupling 1, the body 2 and the arm 3. The body 2 also supports an upright post 5 on which is rotationally mounted a counterbalanced swing arm 6. A torsion spring 7 surrounds the post 5 and is connected betweer; the swing arm 6 and a bracket 8 carried by the fixed arm The swing arm 6 has a spoon-like portion 10, positioned in front of the nozzle 4 so that it will be struck by a jet of water issuing therefrom. The portion of the arm 6 on the opposite side of the post 5 is formed as a counterbalance 11 and has a locking face 12 engageable by a catch head 14 forming part of a sectoring mechanism.

The sectoring mechanism also comprises a lever 15 mounted for turning on a pin 16 carried by the body 2. The lever 15 has an upwardly-extending arm 17 on which the catch head 14 is carried and a downwardly-extending arm 18 positioned between a pair of stops 19 and 20 mounted on the pipe connector 1 and angularly adjustable about the vertical axis thereof relatively to the body 2. The stop 19 is for effecting the engagement of the sectoring mechanism and the other stop 20 is for disengaging the sectoring mechanism.

When the sectoring mechanism is not in operation, a jet of water issuing from the nozzle 4 will enter the bowl 21 of the spoon-like portion 10 and cause the latter, together with the swing arm 6, to turn relatively to the sprinkler body 2 in the anti-clockwise direction, as shown by arrow Z in FIG. 2, against the torsion of the spring 7, until the latter has arrested the arm 6. The stored energy in the spring 7 will then cause the arm 6 to move in a clockwise direction, i.e. opposite to arrow Z, until the arm 6 strikes the bracket 8 carried by the sprinkler body 2. The latter will then move in a short angular step in the clockwise direction, that is opposite to arrow Z. As long as the sectoring mechanism is not in operation this movement will be repeated and the sprinkler body will turn continuously about its axis with a step-by-step angular motion in the clockwise direction.

When the sectoring mechanism has been set to operate by appropriate adjustment of the stops 19 and 20, the sprinkler body 2 will turn in the clockwise direction in angular steps, as described in the preceding paragraph, until the arm 18 strikes stop 19. This will cause the catch head 14 to engage the locking face 12 on the end 11 of to swing arm 6, thereby to lock the latter and the sprinkler body 2 together to prevent their movement out of the path of the jet issuing from the nozzle 4. Thus the jet continuously strikes the spoon-like portion 10, causing the arm 6, together with the sprinkler body 2, to turn rapidly in the anti-clockwise direction, i.e. in the direction of arrow Z, until the arm 18 has struck the other stop 20. When that occurs, the catch head 14 will be disengaged from the locking face 12 and the normal step-by-step angular motion in the clockwise direction, i.e. opposite to arrow Z, will be resumed. As substantially all the water in the jet will strike the bowl 21 of the spoon-like portion 10 during the locked movement of the arm 6 and the sprinkler body 2 in the anti-clockwise direction Z, the sprinkler body 2 will turn rapidly in that direction causing the arm 18 to strike the stop 20' with considerable force. This could lead to damage of the sectoring mechanism.

The spoon-like portion 10 of the known sprinkler illustrated in FIGS. 1 and 2 is of substantially rectangular shape, as viewed from either the front or back of its bowl 21. It has a deflector surface 22 extending substantially across the whole effective width of the spoon-like portion 10 at the end of the latter nearer to the nozzle 4 and a rectangular aperture 23 by which water flowing over the deflector surface 22 will enter the bowl 21.

Substantially the whole of the jet passes through the aperture 23 and enters the bowl 21 and so the full force of the jet pushes the spoon-like portion 10 and hence the whole sprinkler body 2, when the sectoring mechanism is operative, thereby accounting for the considerable force exerted by the arm 18 against the stop 20. An object of the present invention is to modify the spoon-like portion of the known arm shown illustrated in FIGS. 1 and 2 of the accompanying drawings, thereby to reduce the quantity of water entering the bowl of the spoon-like portion and thus to reduce the striking force of the arm 18 against the stop 20. Another object of the present invention is to modify the spoon-like portion of the known arm to improve the water distribution from a sprinkler of either the sectoring kind or the nOn-sectoring kind and including the modified swing arm.

According to the present invention, a swing arm for a rotary water sprinkler has a hub portion by which the arm is securable to the sprinkler for swinging about the axis of rotation of the swing arm, the swing arm also having a spoon-like portion extending outwardly from the hub portion and defining a bowl to be impinged by a jet issuing from a nozzle carried by the sprinkler, a portion of the rearwardly-facing surface of the spoon-like portion being shaped to form a deflector surface against which the jet impinges prior to entering the bowl of the spoon-like portion through an aperture in the said bowl, the aperture extending between the upstream and downstream ends of the bowl with respect to the direction of the jet prior to it impinging the deflector surface, thereby to reduce the effective Width of the bowl transversely to said direction of the jet, and the deflector surface upstream of the aperture extending through substantially the whole width of the spoon-like portion, whereby only part of the jet on leaving the deflector surface will flow through the aperture into the bowl, the remainder being guided by the deflector surface past the spoon-like portion without entering the bowl thereof.

With a swing arm having a spoon-like portion in accordance with the present invention, a part of the jet is deflected by the deflector surface along the back of the spoon-like portion past the aperture and hence produces a reaction component opposing turning movement of the swing arm by the jet and hence serving to reduce the angular velocity of the arm, the remainder of the jet passing through the aperture into the bowl of the spoonlike portion and there being used to effect turning of the arm.

Conveniently, the aperture in the spoon-like portion extends obliquely across the bowl thereof and the deflecting surface is tapered widthwise of the spoon-like portion in the direction of the jet.

The invention also includes a rotary water sprinkler having a swing arm in accordance with the first and the third of the immediately preceding three paragraphs hereof.

By way of example, a swing arm in accordance with the present invention will be compared with the known swing arm illustrated in FIGS. 1 and 2 hereof with reference to the additional accompanying drawings, in which:

FIG. 3 is an elevation of a swing arm having a spoonlike portion in accordance with the present invention;

FIG. 4 is a View, to a larger scale, similar to part of FIG. 2 hereof and showing the spoon-like portion of FIG. 3;

FIG. 5 is a view of the spoon-like portion shown in FIG. 4 in the direction of arrow V therein;

FIG. 6 is a view similar to FIG. 1 showing the swing arm of FIGS. 3 to 5 assembled in a sprinkler having a sectoring mechanism;

FIG. 7 is a view similar to FIG. 1 showing the swing arm of FIGS. 3 to 5 assembled in a sprinkler of the nonsectoring kind;

FIG. 8 is a water distribution diagram obtained by plotting the depth of water discharged by a sprinkler, in-

cluding the known swing arm as shown in FIGS. 1 and 2, against .distance from the axis of rotation of the sprinkler;

FIG. 9 is a similar water distribution diagram for a sprinkler including the swing arm shown in FIGS. 3 to 5, and

FIG. 10 is a diagram showing a grid of four overlapping circular areas of ground irrigated by a rotary sprinkler arranged in four subsequent positions or by four similar rotary sprinklers arranged with their axes of rotation in the four positions illustrated.

The spoon-like portion of the swing arm in accordance with the present invention is shown at in FIGS. 3 to 5 hereof and has a deflector surface having an upstream portion 51, adjacent the nozzle 4, similar to the surface 22 of the known swing arm (shown in FIGS. 1 and 2 hereof) and extending across substantially the whole effective width of the spoon-like portion. In the arm shown in FIGS. 3 to 5 hereof, the deflector surface also has an integral portion 52 of triangular shape extending from the downstream end of the portion 51 towards the downstream end of the spoon-like portion, the portion 52 tapering widthwise in the downstream direction, as best shown in FIG. 3. Downstream of the upstream portion 51 of the deflector surface, there is an aperture 53 effective communication from the deflector surface portions 51, 52 into the bowl 54 of the spoon-like portion 50. The aperture 53 does not extend through the whole effective width of the spoon-like portion immediately downstream of the deflector surface portion 51, as does the aperture 23 in the known swing arm shown in FIG. 1; but instead follows the direction of the oblique edge of the deflector surface portion 52 and extends through substantially the whole length thereof. The width of the aperture 53 is substantially constant widthwise of the spoon-like portion and therefore the bowl 54 is of generally triangular shape, as shown in FIG. 5 and is of smaller surface area than the corresponding bowl 21 of the known arm.

The spoon-like portion 50 is carried by a swing arm, indicated at 55 and, generally similar to the swing arm 6 of FIGS. 1 and 2. When the arm 55 is locked to the sprinkler body in the manner described with reference to FIGS. 1 and 2, the nozzle 4 will discharge against the spoon-like portion; but only part of the jet from the nozzle 4 will pass through the aperture 53 and impinge against the inner face of the bowl 54. The direction of flow of that portion of the jet is indicated by the arrowed line X in FIG. 4. The remainder of the jet is deflected by the surface portions 51 and 52 and flows from the back of the spoon-like portion 50 in the direction of arrowed line Y in FIG. 4. The tangential component causing rotation of the swing arm 55 in the anti-clockwise direction Z, as viewed in FIG. 4, is only derived from the portion of the jet which passes into the bowl 54 and flows along the path indicated by line X in FIG. 4. The remainder of the jet flowing along line Y has a tangential component opposing the tangential component due to the portion of the jet flowing along the path indicated by line X and thus, by using the spoon-like portion 50 instead of the known spoon-like portion 10, the arm 18 shown in FIGS. 1 and 2 will strike the stop 20 with considerably reduced velocity.

FIG. 6 shows the swing arm described with reference to FIGS. 3 to 5 assembled in a rotary Water sprinkler having sectoring mechanism as shown in FIG. 1. The same reference numerals have been used for like parts in FIGS. 1 and 6.

FIG. 7 is a view similar to FIG. 6 showing the swing arm described with reference to FIGS. 3 to 5 assembled in a rotary water sprinkler not having the sectoring mechanism 14 to 20 inclusive. The same reference numerals have been used for like parts in FIGS. 1, 6 and 7.

It has been explained hereinbefore that one reason for providing the aperture and the deflecting surface on the spoon-like portion of the swing arm is to reduce impact of the swing arm on a stop member of the sectoring mechanism of the rotary sprinkler; but it has also been found that the swing arm described with reference to FIGS. 3 to hereof also effects better distribution of water over the area to be irrigated and therefore it can be also used with advantage in a rotary water sprinkler not having sectoring mechanism.

Reference is now made to FIGS. 8 to 10.

With the conventional swing arm shown in FIGS. 1 and 2, the jet of water from the nozzle (not shown) passes in the direction of arrows X through the aperture 23 into the bowl of the spoon-like portion 21, where it is deflected by the inner surface of the bowl. This results in a distribution of water as shown in FIG. 8 having a pronounced dip in depth of water near to the axis of rotation of the sprinkler.

In contradistinction, by using the swing arm in accordance with the present application, as shown in FIGS. 3 to 5, the jet of water is split by the deflecting surface 51 which faces rearwardly of the bowl 50 of the spoon-like portion so that only part of the jet enters the aperture 53 to impinge against the inner surface 54 of the bowl 50. The remainder of the water from the jet is deflected by the deflecting surface 51 to flow past the hack of the bowl of the spoon-like portion 50. In FIG. 5 the arrows X show the flow of the portion of the jet which passes through the aperture 53 to impinge on the inner surface 54 of the bowl 50, whereas the arrow Y shows the part of the portion of the jet which is deflected by the deflecting surface 51 and does not enter the bowl 50. By collecting the water discharged by a rotary sprinkler fitted with the swing arm shown in FIGS. 4 and 5, it has been found that the part of the jet which flows past the back of the bowl 50 in the direction of arrow Y travels further from the axis of rotation of the sprinkler than does the portion which enters into the bowl 50 and is deflected in the direction of arrow X in FIG. 5. This has the result that the dip in the distribution diagram appearing in FIG. 8 does not occur when the swing arm shown in FIGS. 4 and 5 is employed, as illustrated in FIG. 9.

The avoidance of the dip in the distribution diagram is of particular importance when a water sprinkler or sprinklers irrigate an area in a grid formation as shown in FIG. 10, because the hatched areas W close to the axis of rotation of the sprinkler or sprinklers where no overlap of spraying occurs will, in the case of the conventional swing arm, receive a low and insuflicient depth of water, whereas by using a swing arm in accordance with aforesaid co-pending application or this application, where there is no dip in the distribution diagram, as shown in FIG. 9, the areas W will be irrigated with a sufficient depth of water. With a conventional swing arm, the areas W could only be given suflicient water by fitting the sprinkler with an additional nozzle or with devices to spread the jet from a single nozzle.

What I claim as my invention and desire to secure by Letters Patent of the United States is:

1. A swing arm, for a rotary water sprinkler, the swing arm having a hub portion by which the arm is securable to the sprinkler for swinging about the axis of rotation of the swing arm, the swing arm also having a spoon-like portion extending outwardly from the hub portion and defining a bowl to be impinged by a jet issuing from a nozzle carried by the sprinkler, wherein the improvement comprises a portion of the rearwardly-facing surface of the spoon-like portion is shaped to form a deflector surface against which the jet impinges prior to entering the bowl of the spoon-like portion through an aperture in said bowl, the aperture extending between the upstream and downstream ends of said bowl with respect to the direction of the jet prior to it impinging said deflector surface, thereby to reduce the effective width of said bowl transversely to said direction of the jet, and the deflector surface upstream of the aperture extending through substantially the whole width of the spoon-like portion, whereby only part of the jet on leaving the deflector surface will flow through the aperture into the bowl, the remainder being guided by the deflector surface past the spoon-like portion without entering the bowl thereof.

2. A swing arm as claimed in claim 1 in which the aperture in the spoon-like portion extends obliquely across the bowl thereof and the deflector surface is tapered widthwise of the spoon-like portion in the direction of the jet.

3. A rotary water sprinkler including a swing arm as claimed in claim 1, a body having a water-supply throughway therein and a nozzle mounted on said body and connected to said throughway.

4. A rotary water sprinkler including a swing arm as claimed in claim 1, a body having a water-supply throughway therein, a nozzle mounted on said body and connected to said throughway and a sectoring mechanism for locking said swing arm to said body.

References Cited UNITED STATES PATENTS ALLEN N. KNOWLES, Primary Examiner M. Y. MAR, Assistant Examiner US. Cl. X.R. 239233 

